1. in the sense of puzzling
- strange
- puzzling
- curious
- peculiar
- queer
- funny
- weird
- odd
- mystifying
- bizarre
- baffling
- inexplicable
- bewildering
- perplexing
- uncanny
- confusing
- impenetrable
- dark
- unexplainable
- incomprehensible
- Delphic
- unfathomable
- unaccountable
- sibylline
- obscure
- insoluble
- recondite
- arcane
- esoteric
- secret
- cryptic
- occult
- concealed
- hidden
- mystical
- supernatural
2. in the sense of enigmatic
- inscrutable
- enigmatic
- sphinxlike
- secretive
- reticent
- cloak-and-dagger
- discreet
- non-committal
- furtive
- evasive
- covert
- surreptitious
- black
Example Sentences of Mysterious
1. The forest held a mysterious aura.
2. She received a mysterious letter today.
3. He told a mysterious old story.
4. There was a mysterious noise outside.